Saturday, July 9, 2011

Potassium Iodide Pills

Potassium iodide (also called KI) is a salt of stable (not radioactive) iodine. Stable iodine is an important chemical needed by the body to make thyroid hormones.

Potassium iodide is medicinally supplied in 130 mg tablets for emergency purposes in the events below:
Chernobyl nuclear reactor disaster in April 1986
Fukushima Daiichi Nuclear plant damaged in the massive Japanese earthquake in March 2011

In the wake of the nuclear plant meltdown in Japan, Americans are buying up potassium iodide pills (also called iodine pills) to fight off radiation poisoning. The effectiveness of KI as a blocker of thyroid radioiodine uptake is well established. However, it’s only for specific types of exposure. Potassium iodide works only to prevent the thyroid from uptaking radioactive iodine. Potassium iodide has no impact on the uptake by the body of other radioactive materials and provides no protection against external irradiation of any kind nor prevents radiation damage to other parts of the body.

When administered in the recommended dose, KI is effective in reducing the risk of thyroid cancer in individuals or populations at risk for inhalation or ingestion of radioiodines. Specifically, potassium iodide blocks only the thyroid from absorbing radioactive iodine. The thyroid gland cannot tell the difference between stable and radioactive iodine and will absorb both. KI works by saturating the thyroid glands with stable iodine, the thyroid gland becomes “full” and cannot absorb any more iodine. The thyroid gland cannot absorb radioactive iodine if it is saturated with non-radioactive iodine.

IOSAT KI tablets 130mg, ThyroSafe KI pills 65 mg and ThyroShield® KI Oral Solution

Up to date, three companies (Anbex, Inc., Fleming Co, and Recip of Sweden) have met the strict FDA requirements for manufacturing and testing of KI, and they offer products (IOSAT, ThyroShield, and ThyroSafe, respectively) which are available for purchase.

Though the FDA currently requires to state an actual expiration date (5 years from date of manufacture), if kept dry in its packaging, it can last for years. In a recent test, IOSAT™ KI produced 16 years ago were assayed and found to be as effective as the day they were manufactured.

KI tablets are not used as nutritional supplements, since the nutritional requirement for iodine is only 150 micrograms or 0.15 mg of iodide per day.

Friday, July 1, 2011

Methods of Prevention

The thyroid gland in the neck is one of the most sensitive organs in the body to radiation. The thyroid uses iodine normally to make thyroid hormone. The radiation from a nuclear event releases radioactive iodine into the air. Exposure to high levels of radiation — as occurs during a nuclear plant meltdown — can lead to thyroid cancer. Radiation seeps into the body through skin and by breathing it into the lungs. It then travels to the thyroid unless potassium iodide is present to block it.

So how does potassium iodide help?

Taking potassium iodide pills temporarily stops the thyroid. If taken prior to radiation exposure, the iodine pills counter the effect of the radioactive iodine on the thyroid. This helps prevent the development of thyroid cancer down the road. For optimal protection against inhaled radioiodines, KI should be administered before the passage of the radioactive iodine plume, though KI may still have a substantial protective effect even if taken 3 or 4 hours after exposure. Take one dose as soon as possible and then every 24 hours at the same time each day.

In 1982, the U.S. Food and Drug Administration (FDA) approved potassium iodide to protect thyroid glands from radioactive iodine involving accidents or fission emergencies. Usually, only one dose of potassium iodide is needed since a single dose protects the thyroid gland for 24 hours. U.S. FDA-approved dosing of potassium iodide for this purpose is as follows (per 24 hours):

However, some sources recommend alternative dosing regimens. The above dosage is also recommended by WHO. Side effects are unlikely when KI is used at the recommended dose and for a short time. However, some of the possible side effects are skin rashes, swelling of the salivary glands, “Iodism” (metallic taste, burning mouth and throat, sore teeth and gums, symptoms of a head cold, and sometimes upset stomach and diarrhea) and an allergic reaction towards iodine.

Pregnant women should take it for their own protection and for that of the fetus, as iodine readily crosses the placenta. However, because of the risk of blocking fetal thyroid function with excess stable iodine, repeat dosing with KI of pregnant women should be avoided. Lactating females should be take it for their own protection to reduce the radioiodine content of the breast milk, but not as a means to deliver KI to infants, who should get their KI directly.